(*
 * Copyright (c) 2016 - present Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the BSD style license found in the
 * LICENSE file in the root directory of this source tree. An additional grant
 * of patent rights can be found in the PATENTS file in the same directory.
 *)

open! IStd
module F = Format

let tests =
  let open AccessPathTestUtils in
  let x = make_access_path "x" [] in
  let y = make_access_path "y" [] in
  let f_access = make_field_access "f" in
  let g_access = make_field_access "g" in
  let xF = make_access_path "x" ["f"] in
  let xFG = make_access_path "x" ["f"; "g"] in
  let yF = make_access_path "y" ["f"] in
  let xArr =
    let dummy_typ = Typ.mk Tvoid in
    let dummy_arr_typ = Typ.mk_array dummy_typ in
    let base = make_base "x" ~typ:dummy_arr_typ in
    (base, [make_array_access dummy_typ])
  in
  let x_exact = AccessPath.Abs.Exact x in
  let y_exact = AccessPath.Abs.Exact y in
  let x_abstract = AccessPath.Abs.Abstracted x in
  let xF_exact = AccessPath.Abs.Exact xF in
  let xFG_exact = AccessPath.Abs.Exact xFG in
  let yF_exact = AccessPath.Abs.Exact yF in
  let yF_abstract = AccessPath.Abs.Abstracted yF in
  let open OUnit2 in
  let equal_test =
    let equal_test_ _ =
      assert_bool "equal works for bases" (AccessPath.equal x (make_access_path "x" [])) ;
      assert_bool "equal works for paths" (AccessPath.equal xFG (make_access_path "x" ["f"; "g"])) ;
      assert_bool "disequality works for bases" (not (AccessPath.equal x y)) ;
      assert_bool "disequality works for paths" (not (AccessPath.equal xF xFG))
    in
    "equal" >:: equal_test_
  in
  let append_test =
    let pp_diff fmt (actual, expected) =
      F.fprintf fmt "Expected output %a but got %a" AccessPath.pp expected AccessPath.pp actual
    in
    let assert_eq input expected = assert_equal ~cmp:AccessPath.equal ~pp_diff input expected in
    let append_test_ _ =
      assert_eq xF (AccessPath.append x [f_access]) ;
      assert_eq xFG (AccessPath.append xF [g_access])
    in
    "append" >:: append_test_
  in
  let prefix_test =
    let prefix_test_ _ =
      assert_bool "x is prefix of self" (AccessPath.is_prefix x x) ;
      assert_bool "x.f is prefix of self" (AccessPath.is_prefix xF xF) ;
      assert_bool "x is not prefix of y" (not (AccessPath.is_prefix x y)) ;
      assert_bool "x is prefix of x.f" (AccessPath.is_prefix x xF) ;
      assert_bool "x.f not prefix of x" (not (AccessPath.is_prefix xF x)) ;
      assert_bool "x.f is prefix of x.f.g" (AccessPath.is_prefix xF xFG) ;
      assert_bool "x.f.g is not prefix of x.f" (not (AccessPath.is_prefix xFG xF)) ;
      assert_bool "y.f is not prefix of x.f" (not (AccessPath.is_prefix yF xF)) ;
      assert_bool "y.f is not prefix of x.f.g" (not (AccessPath.is_prefix yF xFG))
    in
    "prefix" >:: prefix_test_
  in
  let of_exp_test =
    let f_resolve_id _ = None in
    let dummy_typ = Typ.mk Tvoid in
    let check_make_ap exp expected_ap ~f_resolve_id =
      let make_ap exp =
        match AccessPath.of_lhs_exp ~include_array_indexes:true exp dummy_typ ~f_resolve_id with
        | Some ap ->
            ap
        | None ->
            assert false
      in
      let actual_ap = make_ap exp in
      let pp_diff fmt (actual_ap, expected_ap) =
        F.fprintf fmt "Expected to make access path %a from expression %a, but got %a"
          AccessPath.pp expected_ap Exp.pp exp AccessPath.pp actual_ap
      in
      assert_equal ~cmp:AccessPath.equal ~pp_diff actual_ap expected_ap
    in
    let of_exp_test_ _ =
      let f_fieldname = make_fieldname "f" in
      let g_fieldname = make_fieldname "g" in
      let x_exp = Exp.Lvar (make_var "x") in
      check_make_ap x_exp x ~f_resolve_id ;
      let xF_exp = Exp.Lfield (x_exp, f_fieldname, dummy_typ) in
      check_make_ap xF_exp xF ~f_resolve_id ;
      let xFG_exp = Exp.Lfield (xF_exp, g_fieldname, dummy_typ) in
      check_make_ap xFG_exp xFG ~f_resolve_id ;
      let xArr_exp = Exp.Lindex (x_exp, Exp.zero) in
      check_make_ap xArr_exp xArr ~f_resolve_id ;
      (* make sure [f_resolve_id] works *)
      let f_resolve_id_to_xF _ = Some xF in
      let xFG_exp_with_id =
        let id_exp = Exp.Var (Ident.create_normal (Ident.string_to_name "") 0) in
        Exp.Lfield (id_exp, g_fieldname, dummy_typ)
      in
      check_make_ap xFG_exp_with_id xFG ~f_resolve_id:f_resolve_id_to_xF ;
      (* make sure we can grab access paths from compound expressions *)
      let binop_exp = Exp.le xF_exp xFG_exp in
      match AccessPath.of_exp ~include_array_indexes:true binop_exp dummy_typ ~f_resolve_id with
      | [ap1; ap2] ->
          assert_equal ~cmp:AccessPath.equal ap1 xFG ;
          assert_equal ~cmp:AccessPath.equal ap2 xF
      | _ ->
          assert false
    in
    "of_exp" >:: of_exp_test_
  in
  let abstraction_test =
    let abstraction_test_ _ =
      assert_bool "extract" (AccessPath.equal (AccessPath.Abs.extract xF_exact) xF) ;
      assert_bool "is_exact" (AccessPath.Abs.is_exact x_exact) ;
      assert_bool "not is_exact" (not (AccessPath.Abs.is_exact x_abstract)) ;
      assert_bool "(<=)1" (AccessPath.Abs.( <= ) ~lhs:x_exact ~rhs:x_abstract) ;
      assert_bool "(<=)2" (AccessPath.Abs.( <= ) ~lhs:xF_exact ~rhs:x_abstract) ;
      assert_bool "not (<=)1" (not (AccessPath.Abs.( <= ) ~lhs:x_abstract ~rhs:x_exact)) ;
      assert_bool "not (<=)2" (not (AccessPath.Abs.( <= ) ~lhs:x_abstract ~rhs:xF_exact))
    in
    "abstraction" >:: abstraction_test_
  in
  let domain_test =
    let domain_test_ _ =
      let pp_diff fmt (actual, expected) =
        F.fprintf fmt "Expected %s but got %s" expected actual
      in
      let assert_eq input_aps expected =
        let input = F.asprintf "%a" AccessPathDomains.Set.pp input_aps in
        assert_equal ~cmp:String.equal ~pp_diff input expected
      in
      let aps1 = AccessPathDomains.Set.of_list [x_exact; x_abstract] in
      (* { x*, x } *)
      let aps2 = AccessPathDomains.Set.add xF_exact aps1 in
      (* x*, x, x.f *)
      let aps3 = AccessPathDomains.Set.add yF_exact aps2 in
      (* x*, x, x.f, y.f *)
      assert_bool "mem_easy" (AccessPathDomains.Set.mem x_exact aps1) ;
      assert_bool "mem_harder1" (AccessPathDomains.Set.mem xFG_exact aps1) ;
      assert_bool "mem_harder2" (AccessPathDomains.Set.mem x_abstract aps1) ;
      assert_bool "mem_negative" (not (AccessPathDomains.Set.mem y_exact aps1)) ;
      assert_bool "mem_not_fully_contained" (not (AccessPathDomains.Set.mem yF_abstract aps3)) ;
      assert_bool "mem_fuzzy_easy" (AccessPathDomains.Set.mem_fuzzy x_exact aps1) ;
      assert_bool "mem_fuzzy_harder1" (AccessPathDomains.Set.mem_fuzzy xFG_exact aps1) ;
      assert_bool "mem_fuzzy_harder2" (AccessPathDomains.Set.mem_fuzzy x_abstract aps1) ;
      assert_bool "mem_fuzzy_negative" (not (AccessPathDomains.Set.mem_fuzzy y_exact aps1)) ;
      (* [mem_fuzzy] should behave the same as [mem] except in this case *)
      assert_bool "mem_fuzzy_not_fully_contained"
        (AccessPathDomains.Set.mem_fuzzy yF_abstract aps3) ;
      assert_bool "<= on same is true" (AccessPathDomains.Set.( <= ) ~lhs:aps1 ~rhs:aps1) ;
      assert_bool "aps1 <= aps2" (AccessPathDomains.Set.( <= ) ~lhs:aps1 ~rhs:aps2) ;
      assert_bool "aps2 <= aps1" (AccessPathDomains.Set.( <= ) ~lhs:aps2 ~rhs:aps1) ;
      assert_bool "aps1 <= aps3" (AccessPathDomains.Set.( <= ) ~lhs:aps1 ~rhs:aps3) ;
      assert_bool "not aps3 <= aps1" (not (AccessPathDomains.Set.( <= ) ~lhs:aps3 ~rhs:aps1)) ;
      assert_eq (AccessPathDomains.Set.join aps1 aps1) "{ x*, x }" ;
      assert_eq (AccessPathDomains.Set.join aps1 aps2) "{ x*, x, x.f }" ;
      assert_eq (AccessPathDomains.Set.join aps1 aps3) "{ x*, x, x.f, y.f }" ;
      let widen s1 s2 = AccessPathDomains.Set.widen ~prev:s1 ~next:s2 ~num_iters:10 in
      assert_eq (widen aps1 aps1) "{ x*, x }" ;
      assert_eq (widen aps2 aps3) "{ x*, y.f*, x, x.f }" ;
      let aps_prev = AccessPathDomains.Set.of_list [x_exact; y_exact] in
      (* { x, y } *)
      let aps_next = AccessPathDomains.Set.of_list [y_exact; yF_exact] in
      (* { y. y.f } *)
      (* { x, y } \/ { y, y.f } = { y.f*, x, y } *)
      assert_eq (widen aps_prev aps_next) "{ y.f*, x, y }" ;
      (* { y, y.f } \/ { x, y } = { x*, y, y.f } *)
      assert_eq (widen aps_next aps_prev) "{ x*, y, y.f }" ;
      assert_eq (AccessPathDomains.Set.normalize aps1) "{ x* }" ;
      assert_eq (AccessPathDomains.Set.normalize aps2) "{ x* }" ;
      assert_eq (AccessPathDomains.Set.normalize aps3) "{ x*, y.f }"
    in
    "domain" >:: domain_test_
  in
  "all_tests_suite"
  >::: [equal_test; append_test; prefix_test; of_exp_test; abstraction_test; domain_test]